• Coronary Artery Disease
• Interventional Techniques & Devices Clinical Trials

Professor A. Pieter Kappetein, MD, PhD, Erasmus Medical Center, Rotterdam, The Netherlands, presented the 2-year results from the SYNTAX study (NCT00114972), suggesting that coronary artery bypass grafts (CABGs) may be more appropriate for patients with complex three-vessel (3VD) and/or left main coronary (LM) disease, while percutaneous coronary intervention (PCI) may be an acceptable alternative for patients with less complex disease.

SYNTAX was a prospective, multinational, randomized clinical trial that was designed to compare PCI with CABG for the treatment of de novo 3VD and/or LM disease. All subjects were screened by a cardiac surgeon and an interventional cardiologist. Those who were eligible for either treatment were randomized to PCI or CABG, stratified by LM disease and diabetes. Subjects who were suitable for only one treatment were entered into the appropriate SYNTAX registry. All randomized subjects were assigned a SYNTAX score, a novel angiographic tool that is used to measure the complexity of coronary artery disease based on 9 anatomic criteria, including lesion frequency, complexity, and location (www.syntaxscore.com). Higher SYNTAX scores are indicative of patients with more complex disease and increased treatment challenges.

A total of 1800 patients were randomized at 85 sites (CABG, n=897; PCI, n=903). Subjects were aged a mean of 65 years; approximately 25% had diabetes. Mean total SYNTAX score was 29.1 in the CABG arm and 28.4 in the PCI arm. The mean number of lesions was 4.4 in the CABG arm and 4.3 in the PCI arm. Most patients (∼66%) had 3VD; approximately 34% had LM disease, most with multiple vessel involvement [Serruys PW et al. N Engl J Med 1009].

After 2 years, the primary endpoint of SYNTAX, major adverse cardiac and cerebrovascular events (MACCE; defined as a composite of all-cause death, stroke, myocardial infarction [MI], and repeat revascularization), was significantly (p<0.001) higher in the PCI arm due, in large part, to increased repeat revascularization (PCI 17.4% vs CABG 8.6%). The composite safety endpoint of death/stroke/MI was comparable between the two groups. The rate of MI was significantly increased in PCI patients, whereas stroke remained significantly higher in CABG patients after 2 years of follow-up (Table 1).

The impact of lesion complexity on 2-year clinical outcomes was estimated by examining patient outcomes relative to SYNTAX score tertile (low = 0–22; intermediate=23–32; high ≥33). The rates of MACCE were not significantly different between patients with low SYNTAX scores who were treated with either PCI or CABG (CABG 17.4% vs PCI 19.4%; p=0.63). In patients with intermediate SYNTAX scores, there was a trend toward increased MACCE with PCI (CABG 16.4% vs PCI 22.8%; p=0.06). In the most complex patients (SYNTAX scores ≥33), MACCE was significantly increased in patients who were treated with PCI (CABG 15.4% vs PCI 28.2%; p=0.0001).

In his commentary on the SYNTAX study data, Professor Manuel Attunes, University of Coimbra, Portugal, noted that he expects that the differences in MACCE rates will continue to diverge over time. He cautioned, however, that the application of the SYNTAX results to “real life” should take into account local expertise with both PCI and CABG and that a cost analysis between the two treatments may be warranted, particularly for some centers.

• © 2009 MD Conference Express